The Shimano Ultegra RD-6800 Rear Derailleur features a  redesigned spring mechanism giving the RD-6800 an equal, positive sensation regardless of the direction of your shift, or the size of the sprocket that you're shifting to.
 
Engineering plastic pulley plate
28-32t large cog capacity
Wide link design increases rigidity, reducing deflection for precise shifting and a long service life
11-Speed compatible
New spring mechanism for lighter, shorter and more equal shifting operation
Bearing equipped tension pulley
 
The Shimano Ultegra RD-6800 Rear Derailleur Medium Cage GS version will accept up to a 32T rear sprocket. Average weight: 207g (GS).